Formation of metallic glasses near intermetallics in Zr-Cu and Zr-Cu-Ti systems.

Ph.DDOCTOR OF PHILOSOPH

Plasmonic Tamm states: second enhancement of light inside the plasmonic waveguide

A type of Tamm states inside metal-insulator-metal (MIM) waveguides is proposed. An impedance based transfer matrix method is adopted to study and optimize it. With the participation of the plasmonic Tamm states, fields could be enhanced twice: the ffirst is due to the coupling between a normal waveguide and a nanoscaled plasmonic waveguide and the second is due to the strong localization and field enhancement of Tamm states. As shown in our 2D coupling configuration, |E|^2 is enhanced up to 1050 times when 1550 nm light is coupled from an 300 nm Si slab waveguide into an 40 nm MIM waveguide.Comment: 3 pages, 4 figure

Research on Noise Reduction of Variable Speed Rotary Compressor with Large Capacity

With the increasing speed and capacity of variable-speed rotary compressors, the problem of noise especially low and medium frequency noise in the air conditioning system which can\u27t be solved by wrapping soundproof cotton has became more serious. In this paper, based on the noise problem of the rotor compressor with a working capacity of more than 80CC, the main frequency and the position of the noise source within 1000Hz are confirmed by simulation and experiment. Then on the base of this，the muffler and accumulator are respectively optimized and improved combining with Computer Aided Engineering (CAE) means. The final application results show that the optimized scheme can reduce noise by 6.1dB in 160Hz and 8.9dB in the frequency range of 500Hz to 800Hz, achieving good results

Novel Fast-Speed Partial-Shading-Tolerant Flexible Power Point Tracking for Photovoltaic Systems with Explicit Key Points Estimation

Recent power curtailment-based photovoltaic (PV) flexible power point tracking (FPPT) algorithms mainly adopted intricate curve fitting or sophisticated curve-scanning mecha-nisms to ensure the grid supportive functionalities under partial shading conditions (PSCs), showing the limitations of mathe-matical solidity or system dynamics improvement. Accordingly, a novel fast-speed partial-shading-tolerant FPPT (PST-FPPT) algorithm is proposed in this paper. Regarding the proposed scheme, a modified explicit PV model is developed to express the key operation points with the assistance of several representative current-voltage samples from the initialization process, which is beneficial to computational burden reduction and irradiance sensors removal. Additionally, to guarantee the tracking speed to system dynamics, a set point estimation-based direct voltage regulation strategy is proposed in this paper, eliminating the redundant searching in approaching the predefined power com-mand. Simulation and experimental evaluations under various PSCs and operational circumstances validated the effectiveness of the proposed control